Abstract: A phased array includes a first plurality of radiators having a first polarization and a second plurality of radiators having a second polarization, different from said first polarization. The phased array is constructed such that radiating patterns of the first and second plurality of radiators are congruent. The radiators are constructed so that they radiating apertures thereof can occupy virtually the same space, i.e., the spacing of the radiating elements is less than a wavelength. Other features provided allow this compactness to be achieved. Impedance matching features are integrated into the radiators themselves. The elevation assemblies of the radiators are mated together, and then are coupled across to their respective azimuth assemblies. Two azimuth assemblies for either type of polarization may be provided when monopulse operation is required.

Abstract: A method and system for detecting wire in a terrain avoidance, terrain following, or a terrain obstacle system. Radiant energy pulses orthogonally polarized are alternately transmitted. Selected dimensions of a full scattering matrix of adjacent reflected pulses for a particular range are collected and combined to form a null matrix. A null matrix with the two reflected pulses being within a predetermined distance from one another is detected as a wire.